So I started cold plunges/cold swimming more than ten years ago, at some point started documenting it. And I'm glad I did, as we don't have such winters anymore...
Here you can see some fun evening in the Baltic sea - this type of ice we called mojito - cold plunge and piling in one ;)

Taken with Sprocket Rocket and handhel flash - it was dark so I was actually shooting in bulb mode and capturing nearby area with manually triggered flash :P